INCIDENCE OF CANDIDAEMIA AND ANTIFUNGAL SENSITIVITY IN CRITICALLY ILL PATIENTS

Candidaemia is increasing all over the world in recent years mainly in critically ill patients. Invasive candidiasis is becoming an important nosocomial infection. Bloodstream infections (BSIs) caused by Candida spp are a major cause of morbidity and mortality in immune-compromised hosts. The prevalence of fungal infections has progressively increased, because the population of immune-deficient subjects has expanded due to advances in supportive therapy as well as the number of elderly people in our society. In these patients, the most common infections caused by Candida spp are invasive candidiasis (IC) and candidaemia, The incidence of IC was remarkably consistent in US increasing from 1979 to 2001 of about 300% in parallel with the increase of bacterial infections. The mortality rate resulted to be higher in candidaemia than in bacterial infection. C. albicans was the most frequently isolated fungal species with 43.6% of occurrence followed by C. glabrata ( 26.7%) , C.parapsilosis (16%) , C. tropicalis (10%) ,C. krusei (2%) etc. The distribution of Candida spp is quite different in US and in Europe. In Europe and in Canada, blood-stream infections by Candida are lower than that reported from United States where C. glabrata is the most frequent species among non-albicans Candida. The variation in the frequency of C. glabrata may depend on exposure to azoles especially fluconazole used in prophylaxis in high risk critically ill patients. In any case, a shift to non-albicans species and a growing resistance to the common antifungal drugs have been noticed over the last years. Candida spp is part of the normal flora of human skin and mucosa gastrointestinal tract: the species are differently distributed in the various districts of the organism. Based on experimental studies and using molecular biology techniques, it has been confirmed that the most frequent origins of candidaemia are the gastrointestinal tract (via bacterial translocation) and the skin (in critically ill patients with venous catheters). A model for IC can be explained through the insult on the epithelial cells of gastro-intestinal tract and the use of antibiotics affecting the normal intestinal flora. This may select Candida species promoting the infection , the following translocation from gastro-intestinal tract to bloodstream finally leading to the disseminated disease and eventual colonization of CVC. The connection between intensive care unit (ICU) and fungal infections has been demonstrated in several studies (……). In case of critically ill patients admitted in an ICU, a lot of risk factors are involved such as underlying diseases, presence of venous catheters, parenteral nutrition, use of antibiotics , acute pancreatitis, abdominal surgery etc.. Candida colonization, defined as growth of yeast from non-sterile sites, is usually the first stage for most cases of invasive candidiasis in critically ill patients and it has been considered as an early marker of deep infection. Then previous colonization by Candida in non-sterile sites has been identified as a risk factor for invasive infection. In fact, 60-80% of patients with candidaemia were previously colonized by the same species.